B. Took around half an hour to complete.
The complete predicate includes the verb and the rest of the sentence.
The answer would be : “marathon, he”
The indefinite pronoun neither is always singular.
Neither is the negative counterpart of 'either' which is also singular. The basic principle of Subject-Verb Agreement says that the subject and verb must agree with each other, so you should use a singular verb because 'either' and 'neither' are considered singular; however, this principle is sometimes broken by a plural verb which can be used after 'either' and 'neither' informally.
To combine the ideas to make everyone's dreams come true lol hopefully this helped
